<template>
    <div class="article-container">
        <!-- 1. 导航栏 -->
        <van-nav-bar
            class="page-nav-bar"
            left-arrow
            title="黑马头条"
            @click-left="$router.back()"
        ></van-nav-bar>

        <!-- 2. 主体区域 -->
        <div class="main-wrap">
            <!-- 2.1 加载中 -->
            <div class="loading-wrap" v-if="loading">
                <van-loading color="#3296fa" vertical>加载中</van-loading>
            </div>

            <!-- 2.2 加载完成-文章详情 -->
            <div class="article-detail" v-else-if="result.art_id">
                <h1 class="article-title">{{ result.title }}</h1>
                <van-cell class="user-info" center :border="false">
                    <van-image
                        class="avatar"
                        slot="icon"
                        round
                        fit="cover"
                        :src="result.aut_photo"
                    />
                    <div slot="title" class="user-name">
                        {{ result.aut_name }}
                    </div>
                    <div slot="label" class="publish-date">
                        {{ result.pubdate | relativeTime }}
                    </div>
                    <van-button
                        class="follow-btn"
                        type="info"
                        color="#3296fa"
                        round
                        size="small"
                        icon="plus"
                        >关注</van-button
                    >
                </van-cell>
                <div
                    class="article-content markdown-body"
                    ref="prImage"
                    v-html="result.content"
                ></div>
                <van-divider>正文结束</van-divider>
            </div>

            <!-- 2.3 加载失败：404 -->
            <div class="error-wrap" v-else-if="is404">
                <van-icon name="failure" />
                <p class="text">该资源不存在或已删除！</p>
            </div>

            <!-- 2.4 加载失败：其它未知错误（例如网络原因或服务端异常） -->
            <div class="error-wrap" v-else>
                <van-icon name="failure" />
                <p class="text">内容加载失败！</p>
                <van-button class="retry-btn" @click="loadArticle"
                    >点击重试</van-button
                >
            </div>
        </div>

        <!-- 3. 底部区域 -->
        <div class="article-bottom" v-if="result.art_id">
            <van-button class="comment-btn" type="default" round size="small"
                >写评论</van-button
            >
            <van-icon name="comment-o" color="#777" />
            <!-- 传统方法 -->
            <!-- <collect-article
                :value="result.is_collected"
                :id="result.art_id"
                @input="result.is_collected = $event"
            /> -->
            <!-- 使用 v-model 简化代码结构 -->
            <collect-article
                v-model="result.is_collected"
                :id="result.art_id"
            />
            <!-- <LikeArticle
                :like-count="result.like_count"
                :id="result.art_id"
                @update:like-count="result.like_count = $event"
            ></LikeArticle> -->
            <!-- .sync 语法糖 -->
            <LikeArticle
                :like-count.sync="result.like_count"
                :id="result.art_id"
            ></LikeArticle>
            <van-icon name="share" color="#777777"></van-icon>
        </div>
    </div>
</template>

<script>
import { getArticleById } from "@/api/articles";
import { ImagePreview } from "vant";
import CollectArticle from "@/components/collect-article";
import LikeArticle from "@/components/like-article";
export default {
    name: "ArticleDetail",
    props: {
        id: {
            type: [String, Number], // 既可以是数字类型, 也可以是字符串类型
            required: true,
        },
    },
    data() {
        return {
            result: {}, // 内容
            loading: true, // 是否加载文章数据中,
            is404: false, // 是否404错误
        };
    },
    created() {
        this.articleInfo();
    },
    components: {
        CollectArticle,
        LikeArticle,
    },
    methods: {
        async articleInfo() {
            try {
                this.loading = true;
                // 随机错误
                // if (Math.random() > 0.5) {
                //     JSON.parse("abc");
                // }
                this.result = (await getArticleById(this.id)).data;
                setTimeout(() => {
                    this.previewImage();
                }, 0);
            } catch (error) {
                // 网络错误或者404找不到
                if (error.response && error.response.status === 404) {
                    // 找不到页面
                    this.is404 = true;
                }
            } finally {
                this.loading = false; // 无论是否加载成功都要关闭
            }
        },
        loadArticle() {
            // 点击重试
            this.articleInfo();
        },

        previewImage() {
            // 获取所有图片DOM元素组成的数组
            const imgDoms = this.$refs["prImage"].querySelectorAll("img");
            // 遍历所有DOM添加点击事件
            const imgUrls = [];
            imgDoms.forEach((imgDom, index) => {
                imgUrls.push(imgDom.src);
                imgDom.onclick = () => {
                    ImagePreview({
                        images: imgUrls,
                        startPosition: index,
                    });
                };
            });
            // 触发回调函数，
        },
    },
};
</script>

<style scoped lang="less">
@import url("./github-markdown.css");
// @import url("./vueCode.css");
.article-container {
    .main-wrap {
        position: fixed;
        left: 0;
        right: 0;
        top: 92px;
        bottom: 88px;
        overflow-y: scroll;
        background-color: #fff;
    }
    .article-detail {
        .article-title {
            font-size: 40px;
            padding: 50px 32px;
            margin: 0;
            color: #3a3a3a;
        }

        .user-info {
            padding: 0 32px;
            .avatar {
                width: 70px;
                height: 70px;
                margin-right: 17px;
            }
            .van-cell__label {
                margin-top: 0;
            }
            .user-name {
                font-size: 24px;
                color: #3a3a3a;
            }
            .publish-date {
                font-size: 23px;
                color: #b7b7b7;
            }
            .follow-btn {
                width: 170px;
                height: 58px;
            }
        }

        .article-content {
            padding: 55px 32px;
            /deep/ p {
                text-align: justify;
            }
        }
    }

    .loading-wrap {
        padding: 200px 32px;
        display: flex;
        align-items: center;
        justify-content: center;
        background-color: #fff;
    }

    .error-wrap {
        padding: 200px 32px;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        background-color: #fff;
        .van-icon {
            font-size: 122px;
            color: #b4b4b4;
        }
        .text {
            font-size: 30px;
            color: #666666;
            margin: 33px 0 46px;
        }
        .retry-btn {
            width: 280px;
            height: 70px;
            line-height: 70px;
            border: 1px solid #c3c3c3;
            font-size: 30px;
            color: #666666;
        }
    }

    .article-bottom {
        position: fixed;
        left: 0;
        right: 0;
        bottom: 0;
        display: flex;
        justify-content: space-around;
        align-items: center;
        box-sizing: border-box;
        height: 88px;
        border-top: 1px solid #d8d8d8;
        background-color: #fff;
        .comment-btn {
            width: 282px;
            height: 46px;
            border: 2px solid #eeeeee;
            font-size: 30px;
            line-height: 46px;
            color: #a7a7a7;
        }
        .van-icon {
            font-size: 40px;
            .van-info {
                font-size: 16px;
                background-color: #e22829;
            }
        }
    }
}
</style>
